Almost every child goes through a certain amount of teasing or bullying at some point in their lives, but often it can be those who are obviously different who are the most at risk of this. The best thing that you can do is to try and speak to the school that your son is joining. They can make sure that his class understand his disability, but also that they understand that your son is able to have fun with them and make friends just as much as they are. Often, if children can be educated about a difference at a young enough age, they will be able to overcome it and make friends just as they would if they not have this condition. Be there for your son, and keep an eye out for the signs, but there is no reason that he shouldn't be able to go to school and enjoy himself like the other children.